Loading...

Effect of silicon carbide nanoparticles on hot deformation of ultrafine-grained aluminium nanocomposites prepared by hot powder extrusion process

Mobarhan Bonab, M. A ; Sharif University of Technology

861 Viewed
  1. Type of Document: Article
  2. DOI: 10.1080/00325899.2016.1201333
  3. Publisher: Taylor and Francis Ltd
  4. Abstract:
  5. The flow behaviour of Al–SiC nanocomposites prepared by mechanical milling and hot powder extrusion methods was studied at different temperatures (350–500°C) and strain rates (0.005–0.5 s−1). The flow of the Powder metallurgy nanocomposites exhibited a peak stress followed by a dynamic flow softening behaviour. It was shown that mechanical milling increased high-temperature strain rate sensitivity of ultrafine-grained (UFG) aluminium while decreasing its flow dependence to temperature. Constitutive analysis of the hot deformation process by Zener–Hollomon parameter (Z) also indicated a remarkable increase in the deformation activation energy (about 40%). Likewise, SiC nanoparticles (up to 2vol.-%) were shown to contribute in the high-temperature strengthening of UFG aluminium with a significant effect on its thermal stability. The findings were explained based on the pinning effect of hard nanoparticles on grain boundaries and mobile dislocations as well as microstructure stabilisation at elevated temperatures
  6. Keywords:
  7. Activation energy ; Aluminium nanocomposite ; Constitutive analysis ; Hot deformation ; Powder extrusion ; Activation analysis ; Aluminum ; Chemical activation ; Deformation ; Extrusion ; Grain boundaries ; Hot working ; Mechanical alloying ; Milling (machining) ; Nanocomposites ; Nanoparticles ; Powder metallurgy ; Silicon carbide ; Carbide nanoparticles ; Deformation activation energy ; Elevated temperature ; Hot deformation process ; Strain rate sensitivity ; Ultra-fine grained ( UFG) ; Strain rate
  8. Source: Powder Metallurgy ; Volume 59, Issue 4 , 2016 , Pages 262-270 ; 00325899 (ISSN)
  9. URL: http://www.tandfonline.com/doi/abs/10.1080/00325899.2016.1201333